Nguyen HV - Using data from the nationally representative Canadian Tobacco, Alcohol and Drugs Survey (2013-2017) and Canadian Student Tobacco, Alcohol and Drugs Survey (2014-2017), the author conducted this quasi-experimental difference-in-differences and triple-differences study to explore the relationship of banning electronic cigarette (e-cigarette) sales to minors in Canada with e-cigarette use among youths and the mechanisms through which a ban might be linked to their e-cigarette use. Findings suggested an association of banning e-cigarette sales to minors with a significant decline in the rate of increase in e-cigarette use by youths. However, the overall rise in e-cigarette use was not reversed by this policy alone. Supplementing this policy with other measures that can decrease young people’s wish to get e-cigarettes through social sources was suggested. An illustration of such a measure is a ban on e-cigarettes with flavors that appeal to youths and children.